Newbie Question about Food Safe

I'm sure that one of the major reasons for restaurants not using earthenware (in this country) is that it is not nearly as sturdy as stoneware or porcelain. That beautiful, expensive Italian majolica you bought on your last trip to Italy chips very, very easily. I have had food served me in Mexico and Greece on earthenware, its sort of a substitute for polystyrene in some places - cheap, easily replaced when damaged (I'm not talking about that Italian majolica here).

My email to the FDA:In going through the food contact substance regulations it seems that these all refer to chemical substances that could leach out of the product, not how well they can be cleaned/sterilized to prevent bacterial growth. Is there a section of the regulations that discusses this, or are items that cannot be cleaned well simply classified as single use items, like paper plates and such? Does one have to prove that reusable items are in fact reusable, that they can be cleaned?Their response:Mr. Estrick, Not that I know of. The regulations do not get that specific. There are commonly understood safe food handling practices that should be applied.Having worked in many restaurants in the past, I would interpret this standard to mean that porous dishes do not meet the standard for safe food handling practices. The only way you could possibly sterilize a porous dish would be to soak it in a bleach solution, like you have to do with rags/towels used in a commercial kitchen. Of course, then you'd have to get the bleach out. Finally found this is from the food service sanitation code for the state of Illinois:

Section 750.600 General - MaterialsMulti-use equipment and utensils shall be made and repaired with safe, non-toxic materials, including finishing materials, shall be corrosion resistant, non-absorbent, smooth, easily cleanable, and durable under conditions of normal use. Single-service articles shall be made from clean, sanitary, safe, and non-toxic materials. Equipment, utensils, and single-service articles shall not impart odors, color, or taste, nor contribute to the contamination of food.

So, knowing that restaurants can't legally use non-vitrified ceramic ware due to its porosity and inability to be effectively cleaned, should potters be selling it? We strive to meet the other standard of food safety regarding leaching of toxic chemicals, so should we hold ourselves to this standard as well?

Following your interpretation, we would not be able to use any type of clay . . . all clays, to some extent, are absorbent. While porcelains often have an absorbency of less than 1 percent, that less than 1 percent is still absorbent. If the expectation is non-absorbent, then all clays fail. No wooden bowls or utensils, either -- tell the wood turners they are our of business, too. Might as well move on to glass -- that is non-absorbent.

I think you are misreading the context of "non-absorbent". As I read the Illinois code, they are telling me (and maybe only me) that equipment and utensils used in food preparation and serving should not be able to absorb any of the foods they are serving, and with respect to dishes and bowls, that would be surface that comes in contact with food; I can almost guarantee they were not thinking about the absorbency of a pot from water in a dish washer. A clay bowl, properly glazed (e.g., durable and stable, perhaps as defined by Hesselberth and Roy), would satisfy that requirement. An unglazed bowl -- whether of earthenware, stoneware, or porcelain -- would not, even if fired to vitrification because even vitrified there may be some absorption (e.g., less than 1 percent as advertised by clay makers). And, the code writers threw in another undefined stipulation . . . non-absorbent "under conditions of normal use."

Absent a definition of what "non-absorbency" is, e.g., 0%, 1%, 2%, 11%, etc., the code is clear as mud, at least to me.

Following your interpretation, we would not be able to use any type of clay . . . all clays, to some extent, are absorbent. While porcelains often have an absorbency of less than 1 percent, that less than 1 percent is still absorbent. If the expectation is non-absorbent, then all clays fail. No wooden bowls or utensils, either -- tell the wood turners they are our of business, too. Might as well move on to glass -- that is non-absorbent.

I think you are misreading the context of "non-absorbent". As I read the Illinois code, they are telling me (and maybe only me) that equipment and utensils used in food preparation and serving should not be able to absorb any of the foods they are serving, and with respect to dishes and bowls, that would be surface that comes in contact with food; I can almost guarantee they were not thinking about the absorbency of a pot from water in a dish washer. A clay bowl, properly glazed (e.g., durable and stable, perhaps as defined by Hesselberth and Roy), would satisfy that requirement. An unglazed bowl -- whether of earthenware, stoneware, or porcelain -- would not, even if fired to vitrification because even vitrified there may be some absorption (e.g., less than 1 percent as advertised by clay makers). And, the code writers threw in another undefined stipulation . . . non-absorbent "under conditions of normal use."

Absent a definition of what "non-absorbency" is, e.g., 0%, 1%, 2%, 11%, etc., the code is clear as mud, at least to me.

I'm not thinking about dishwasher use, just food use. I think it's safe to say that what we typically regard as 'vitrified' does not fall into the category of 'porous' or they wouldn't allow any dishes whatsoever. And their stipulation of 'normal use' would also make 'vitrified' ware safe, because under normal use it wouldn't be in contact with food long enough to absorb anything. There is a standard, even if it is a bit muddy. It's clear to me that their definition of porous means something that takes in liquid easily, or what people generally regard as absorbent.

You mention properly glazed ware would pass the test. I agree completely. My issue is with a glaze on a porous body that has crazed and allows liquids to penetrate into the walls of the pot, which would then meet their (muddy) definition of porous and not easily cleanable. Also, in a restaurant situation where dirty plates are stacked before washing, the unglazed foot would be in contact with food, therefore soaking up liquids. Unglazed ware would never meet their definition of smooth, regardless of vitrification.

Dare I mention that almost NO studios potters supply dishware to restaurants? I heard one such potter speak at the Alabama Clay Conference and she said she was the only one she had ever seen at their industry shows. She had to hand her plate to the buyer who then dropped it on the floor. The dishes had to pass all of their health and safety checks.
To supply a decent sized restaurant you would need a team of throwers or a ram press or three. They break, chip and otherwise lose a lot of dishes per day. Most restaurants cannot afford to buy/break $20 plates.

In reality, the higher end chain stores are selling low fired, decorated wares with zero qualms. I see glazed terra cotta wares for sale. I see sets of dishes with crackled glaze in my local department store. It seems impossibly confusing to me.

Chris Campbell

Contemporary Fine Colored Porcelain
www.ccpottery.com

TRY ... FAIL ... LEARN ... REPEAT

" ... If a sufficient number of people are different, no one has to be normal"
Fredrick Bachman

"In reality, the higher end chain stores are selling low fired, decorated wares with zero qualms. I see glazed terra cotta wares for sale. I see sets of dishes with crackled glaze in my local department store. It seems impossibly confusing to me. "

Good point, Chris!And we also have to worry about lightning, and sharks, and alien abduction. (also, the Mad Cows are baaaack!)

Newbie, too! Just taking baby steps into the pottery world (addictive!) and I'm using these boards to gain informative knowledge, in tandem with actual hands on experience. I came across this thread while investigating different types of food safe clay and firing methods. All the posts are helpful, interesting and appreciated.

Just wondering (regarding earthenware / unglazed clay pots and food safety) how cooking with Romertopf and other similar clay pots (commercial or hand thrown) relates to this thread. I have cooked with this type clay pot in the past but the cleaning of same was just too exhausting to make it worth my while - too much food getting into porous crevices. I was also concerned about food safety issues. The instructions state the pot is to be submerged in water (activating the porous feature and allowing steam to produce cooking effect) before use and that the pot is be heated at a high temperature during the cooking cycle, high enough to kill off the 'bad' bacteria. However, most people I know who have used this type clay pot cooking, usually let the pot sit for long periods of time after cooking thus allowing for the possibility of food bacteria to grow and harbor. With millions of these pots for sale, and in use, how is this unglazed earthenware pot any different from the thrown earthenware food safety concern being posed?

One other thing to remember...not all glazes (cone 06 OR cone 6) are food safe, whether they're crazed or not. Commercially prepared glazes are labeled for food safety. I do remind students that the label applies only to that specific glaze used by itself and fired properly. If one glaze is layered over another, it will chemically alter both glazes which could change the food safety rating. Do I tell them not to layer glazes? Of course not, that would ruin a lot of fun. But I do tell them how to do simple leaching tests (sliced lemon OR white vinegar) if they're concerned.

So, knowing that restaurants can't legally use non-vitrified ceramic ware due to its porosity and inability to be effectively cleaned, should potters be selling it? We strive to meet the other standard of food safety regarding leaching of toxic chemicals, so should we hold ourselves to this standard as well?

Note that the FDA (and California) regulations for lead and cadmium apply to all food use wares sold. The other standards you are looking at apply onlt to matgerials USED IN THE FOOD SERVICE INDUSTRY, not for household use. The demands an usage are QUITE different.

Just wondering (regarding earthenware / unglazed clay pots and food safety) how cooking with Romertopf and other similar clay pots (commercial or hand thrown) relates to this thread. I have cooked with this type clay pot in the past but the cleaning of same was just too exhausting to make it worth my while - too much food getting into porous crevices. I was also concerned about food safety issues. The instructions state the pot is to be submerged in water (activating the porous feature and allowing steam to produce cooking effect) before use and that the pot is be heated at a high temperature during the cooking cycle, high enough to kill off the 'bad' bacteria. However, most people I know who have used this type clay pot cooking, usually let the pot sit for long periods of time after cooking thus allowing for the possibility of food bacteria to grow and harbor. With millions of these pots for sale, and in use, how is this unglazed earthenware pot any different from the thrown earthenware food safety concern being posed?

I can't find anything at the Romertopf site, but I know the unglazed bakers/stones/etc from Pampered Chef are *stoneware* -- not earthenware. I'd bet the Romertopf is also stoneware (of some ilk) as well -- since it's fired to a higher temperature, it's more durable in the long run and doesn't hold as much water as earthenware does. Not as porous means not as many nooks and crannies for bacteria to hide.

From what I've read, part of the allure of unglazed stoneware is that, over time and with regular use, it will become "seasoned" -- it will become a little more non-stick and (according to some sources) enhance the flavor of the food you're cooking...kind of like cast iron skillets.

Of course, whether that's true or not, I haven't had the chance to find out.

Hi, Maybe I'm the only microbiologist/potter? Bacteria are tiny! (from http://science.howst...copic/cell1.htm) " A typical human cell might be one-tenth of the diameter of your hair (10 microns).... An Escherichia colibacterium ... is about one-hundredth the size of a human cell (maybe a micron long and one-tenth of a micron wide), so it is invisible without amicroscope. " So, like angels on the head of a pin, you can easily have millions of bacteria in a tiny crack in a pot.mss

John, after reading that article, it makes me think of all the other articles, and news stories, that talk about how harmful bacteria and "germs" are just everywhere. That's the biggest problem in my opinion. You have news agencies, looking for something to report, and R&D and marketing branches of companies, looking for a new product they can hock, that focuses on the demand for a solution to a new problem.

I was washing the dishes the other day, when I remembered a news story, about how "dirty" a dish sponge can be, because it holds on to bacteria and such. I'm not saying, that's not true, but I'm not going to microwave my sponge, as they recommend" to kill off the little beasties. The way I see, unless I'm going around mopping up poultry juices constantly, my sponge is relatively clean, or at least not contaminated with anything that's going to harm me or my family. And unless people want to live their lives in a "Clean Room", or start scrubbing their dish/ silverware and counter tops with irradiated bleach and fire, we all need to relax, and realize that our immune systems work pretty well on their own.